They are autotrophic organisms.

Succession showing changes in communities at a place is called

The organisms living at the bottom of a water body are known as:

Out of the total cost of various ecosystem services, the soil formation accounts for $P$, while contributions of other services like recreation and nutrient cycling are less than $Q$ each. The value of climate regulation and habitat for wildlife is about $R$ each. Identify $P, Q,$ and $R$.

The study of Biogeochemical cycles is called Biogeochemistry. Its father is Vernadsky. It involves:

An ecosystem,such as an aquarium,is self-sustaining if it involves the interaction between organisms,a flow of energy,and the presence of